1. Field of the Invention
The present invention relates to a portable information terminal, which accepts data entries with a pen, etc.
2. Description of the Related Art
A portable information terminal including a wide display screen on its top surface and having a function of accepting entries with a pen, etc., without any keyboard is becoming widespread in recent years, and portable information terminals of a palm-size type with a limited processing capacity and a note-size type with a processing capacity comparable to that of a personal computer, etc., are known.
Such a portable information terminal uses a detector called a “tablet,” “digitizer” or “coordinate reader,” etc., to accept data entries using a dedicated pen or a finger and this detector detects the position of the dedicated pen or finger and obtains a position signal, and specifies the position pointed by the dedicated pen or finger using the position signal.
There are plural types of such detectors with different systems of detecting the position of the dedicated pen or finger, and for example, a type of detector called a “touch panel” using a resistor film whose resistance value changes when it is touched by a finger and a type of detector detecting the position or state of the dedicated pen using principles of electromagnetic induction are known as such detectors. These plural types of detectors have their respective advantages and disadvantages; for example, a resistor film type detector needs no dedicated pen and allows data entries using a finger, etc., but it provides only information corresponding to the position of the screen touched by the finger. On the other hand, an electromagnetic induction type detector can obtain information on the strength or inclination of a pressing force with which the screen is pressed or information on the fact that a key provided for the dedicated pen is clicked, etc., too, but it cannot be used to enter data without the dedicated pen.
Manufacturers of portable information terminals may manufacture only one model having one detector selected from among these plural types of detectors or may manufacture a plurality of models with different types of detectors. At the time of manufacturing a plurality of models, it is preferable that those portable information terminals have a structure with a minimum number of differences among models in a parts configuration.